Tile Calculator

Estimate tile count from area, tile dimensions and waste.

What this calculator measures

Tile layouts are affected by grout joints, cuts, pattern, borders and breakage. A professional layout can produce a different count from a purely geometric estimate.

Tile count = floor area ÷ tile area, with waste applied before rounding up. The result is intended to be understandable enough to compare against a drawing, material list or supplier quotation. It does not hide unit conversions or add unexplained corrections.

How the calculation works

The calculator starts with the physical dimensions you enter. Units are converted where required before the geometry is applied. When a waste or adjustment percentage is available, it is calculated after the base quantity so the two figures remain distinguishable. This makes it possible to see whether a change came from the project measurement or from the ordering allowance.

Worked example

Using a 14 ft × 12 ft floor with 12 in × 24 in tile, 12 % allowance, the calculator returns:

The area is 168 ft² and each tile covers 2 ft², so the bare count is 84 tiles; with 12 % for cuts and breakage the estimate is 95 tiles. Large-format tile in a running bond hides fewer offcut reuse opportunities than grid layouts, which is why the allowance sits above the plain 10 %.

Reading the result: the first line is always the geometric base quantity — the number the drawing could defend — and any allowance line sits below it, never inside it. If a supplier's number disagrees with the base line, the argument is about geometry or units; if it disagrees with the allowance line, the argument is about waste policy. Keeping the two separate is the whole point.

Inputs, field by field

• Area length and width (ft): Measure each rectangle separately. Border courses, niches and shower walls should each be their own calculation rather than one blended figure.
• Tile dimensions (in): Enter the labeled tile size in inches. A 12 × 24 tile covers 2 ft² exactly; a 9 × 36 plank covers 2.25 ft² — the module drives the count.
• Grout joints: Joints add a little width per tile, slightly lowering counts. For planning, the tile's bare area is the conservative choice and the waste factor absorbs the difference.
• Waste (%): 10 % for straight grid layouts, 12–15 % for running bond, large formats and diagonal patterns, more for intricate borders and Schluter or niche work.
• Layout pattern: The count assumes a basic parallel layout. Herringbone, basketweave and border-infield patterns change both the waste factor and the module, so run those layouts as their own calculation rather than stretching this one. Whatever the pattern, buy every tile for the visible plane from a single lot at the same time.

Why the inputs matter

Each field represents a dimension or assumption that changes the result. Length and width control area; thickness or depth controls volume; spacing controls the number of repeated components; coverage controls how much surface a product can cover; and waste changes the planning quantity without changing the underlying geometry. Entering a rounded number is acceptable for an early estimate, but actual procurement should use measured conditions and product-specific information.

Units and conversion checks

Construction calculations frequently mix feet and inches. BuildNumeris converts these values explicitly before multiplying. For volume, remember that cubic yards and cubic feet are not interchangeable: one cubic yard contains 27 cubic feet. Area uses square units and volume uses cubic units. A unit error can be much larger than a rounding error, so checking the displayed intermediate quantity is an important part of reviewing the result.

Common mistakes with this calculation

• Buying exactly the tile count and having no spares when a tile cracks months later — production lots drift.
• Underestimating waste on diagonal layouts, where every edge tile is a cut on the diagonal.
• Forgetting the shower or backsplash areas are separate substrates needing their own membrane and thinset quantities.
• Mixing calibers or lot numbers across the same visible plane.
• Treating accent, border and trim tiles as interchangeable with field tile — they are separate products with separate counts.
• Applying a waste percentage twice — once inside a dimension and once in the percentage field.
• Relying on a quantity estimate as if it were structural or code design.

Ordering and materials

Round up to full boxes and keep attic stock. Alongside tile, order thinset matched to the tile size (large-format mortar for big planes), grout calculated from joint width and tile depth, spacers, leveling clips if the specification calls for lippage control, membrane for wet areas, and bullnose or trim profiles for exposed edges.

What this calculator does not decide

This tool does not determine structural adequacy, required reinforcement, soil capacity, design loads, engineering details, local building-code compliance or manufacturer installation requirements. Those decisions can depend on factors that are not represented by a simple quantity formula. Where safety or regulated construction is involved, the project documents and qualified professionals take precedence.

Field verification checklist

Dry-lay a few rows before committing adhesive and confirm the layout minimizes sliver cuts at the perimeter. After grouting, compare boxes used against the estimate and log the waste factor by layout type — grid, bond, diagonal — for future rooms.

Related BuildNumeris tools

Construction estimates are interconnected: a concrete project pulls in gravel, rebar and excavation numbers; a roof package chains pitch, area and rafter length; a wall sequence runs from framing through drywall to paint. Open the related tools below to build a connected takeoff.

Practical workflow

Measure first, select the correct units, enter the dimensions, review the base quantity, decide whether a waste allowance is appropriate, and then compare the result with project documentation. Save or copy the result if you are building a larger estimate. When conditions change, recalculate rather than manually editing the old number.